Summary

In the coming years, NASA’s Curiosity rover will pass rocks on Mars that, seen from orbit, seem to host mysteriously intermittent dark streaks—perhaps marking seasonal water seeps that could host martian life. But NASA’s planetary protection office, charged with keeping earthly microbes from colonizing other bodies, has said it may nix a visit. It fears that Curiosity could contaminate this so-called special region because the rover was not fully sterilized before launch. Many planetary scientists, however, believe that now is the time to loosen restrictions on visiting these areas, before human exploration contaminates the planet. And, after years of stasis, the planetary protection office seems primed for a shakeup, thanks to an internal move and potential change in leadership, along with outside review of its policies by independent scientists.